The demand for propylene impact copolymers with low volatile organic compound content continues to increase as the need for more sophisticated polymers continues to grow. The level of volatile organic compound or (VOC) content of a polymer determines how much VOC evaporates or vaporizes readily under normal or slightly elevated conditions. It is difficult to produce low-VOC-content propylene impact copolymers directly by polymerization. Conventional propylene impact copolymers typically undergo subsequent purge processes to lower the VOC content to acceptable levels.
Desirable is a polymerization process for the production of a propylene impact copolymer with improved properties and a low-VOC-content propylene impact copolymer in particular. Further desired is a process for the production of a low-VOC-content propylene impact copolymer that does not require subsequent purge processing to lower the VOC content.